Defence Minister Yutthasak Sasiprapa has rejected the navy's plan to pay 7.5 billion baht for six used submarines from Germany and questioned the cost-effectiveness and transparency.

He said yesterday a defence scrutiny committee he appointed had resolved to return the project to the navy for review. Gen Jongsak Panichkul, adviser to the defence minister, is chairing the committee, which also includes former navy chief Adm Prasert Boonsong.

"I want a review on the cost-effectiveness," Gen Yutthasak said. "The past government approved the establishment of a submarine fleet and the recruitment of personnel has been completed but transparent procurement has yet to be done."

He said he was not concerned about the Sept 30 deadline that Germany had set for the navy to confirm the purchase of its used U206A submarines. He said the German navy could be asked to extend the deadline.

"But if Germany refuses to extend the deadline, it will be up to the navy to propose submarines from any country for my consideration," the defence minister said. He is open to either new or used vessels.

A navy source said the defence scrutiny committee had recommended submarines from Russia, China and South Korea.

"The navy will let politicians make the choice," the source said. "It will just wait."

He said the German submarines were the best choice in terms of practicality for study, training and price.